Causality between iron overload and osteoarthritis a Mendelian randomization study

Abstract

Objective:We found a significant increase in the incidence of osteoarthritis in patients with iron overload, and conducted Mendelian randomization (MR) analysis to investigate the causal effect of iron overload on osteoarthritis and hip arthritis. Methods: Genome-wide association study (GWAS) data of liver iron content (LIC) and osteoarthritis (OA) and hip arthritis (HOA) were obtained. Single nucleotide polymorphisms (SNPs) were used as instrumental variables and sensitive SNPS were selected for analysis. The inverse variance weighting method (IVW), weighted median method (WM), MR-Egger regression method and other methods were used to conduct MR Analysis of the two samples, and the OR value was used to evaluate the causal [i]relationship between LIC, OA and HOA. Results: In LIC and OA, the p values of IVW model, WM model and MR-Egger model were all <0.05. IVW results were as follows: OR=1.005, 95%CI was 1.001-1.010 P=0.012; Among LIC and HOA, the p values of IVW model, WM model and MR-Egger model are all <0.05, and the result of IVW is: OR=1.184, 95%CI is 1.092-1.285P =4.79×10-5. MR Egger and IVW methods are used to test the heterogeneity, and the results are as follows: there is heterogeneity between LIC and OA (p <0.05), but no heterogeneity between LIC and KOA (p>0.05). Sensitivity analysis by leave-one-out method showed that the results were stable. Conclusion: There is causal relationship between LIC and OA and KOA, and the probability of suffering from OA or HOA increases with the improvement of LIC.